Answer:
4.775
Step-by-step explanation:
Answer:
x=3
Explanation:
Let's write an equation for the area of this figure.
This figure can be divided into 2 rectangles, a vertical and horizontal rectangle.
Area of rectangle= length× breadth
Area of vertical rectangle= 6x
Length of horizontal rectangle= (7 -x) cm
Area of horizontal rectangle= x(7-x)
Since total area= 30 cm^2,
6x+ x(7-x)= 30
6x +7x -x^2= 30 (expand)
-x^2 +13x-30= 0 (bring all terms to one side)
x^2 -13x +30= 0 (divide by -1)
(x -10)(x -3)= 0 (factorise)
x -10= 0 or x -3= 0
x= 10 or x= 3
(reject)
We reject x=10 since from the diagram, x cm is less than 6cm.
I don't think you're stupid. ^^
Let's take the third term, 8. If n=3, then an should be 8.
The first answer gives 15+2.5*3=22.5.
The second answer gives 15.5+2.5=23.
The third answer gives 15-2.5*3=7.5.
The fourth answer gives 15.5-2.5*3=8.
Choice 4 is correct.
Let's try to actually find the equation on our own.
The equation for an arithmetic series is an=a0+dn where a0 is the term that comes before the first term.
The first term given is 13 and it decreases by 2.5 each time so n=-2.5 and the term that would be before 13 is 15.5.
Thus the equation is an=15.5-2.5n
Answer:
let me answer this and i will come back
Step-by-step explanation:
You need one equation for the physical nickels and dimes, which total to 21:
n+d=21
Secondly, you need one equation for the numerical value of those nickels and dimes. We know nickels are worth $0.05 and dime are worth $0.10:
.05n+.1d=1.70